Physical Sciences and Mathematics Commons^™

Mojave Applied Ecology Notes Spring 2008, Lesley Defalco, E. Cayenne Engel, Scott R. Abella, Jessica E. Spencer, Jill E. Craig

Mojave Applied Ecology Notes

Post-fire restoration, fire chronosequence study, Joint Fire Science update, Weed Sentry program and DNWR surveys

Plant Community Response To Fire: A Chronosequence Study, Scott R. Abella, E. Cayenne Engel

Public Policy and Leadership Faculty Publications

Fires are becoming more prevalent events across the landscape in the southwestern US. Over the next several decades the already arid southwest is predicted to become warmer and drier, with longer summers, and an increase of “extreme” weather events such as lightening inducing thunderstorms. While the “hotter and drier” forecast may indicate less abundant plant life, and thus less available biomass for fuel, exotic invasive plant species are becoming more dominant across the landscape with increases in human travel and commerce. Exotic species (particularly many of the invasive grasses) are adding fuel for the fires to burn when the annuals …

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Quarterly Progress Report, January 1— March 31, 2008, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• The Weed Sentry program surveyed 104 miles of transportation corridors on federal land in Clark County for incipient populations of exotic plants.
• Seven manuscripts attained in-press or published status and two manuscripts were submitted for review this quarter. Among other in-press manuscripts, are one documenting Sahara mustard germination patterns (Western North American Naturalist), one assessing exotic species distributions in Clark County (Environmental Monitoring and Assessment), and another is a synthesis of burro effects on Mojave Desert vegetation (Environmental Management).
• Staff delivered four presentations this quarter at conferences or at agency meetings. Twenty-six Las Vegas bearpoppy sites were assessed …

Exotic Annual Plant Invasions And Their Relationships To Roads And Native Perennial Species In The Mojave Desert, Southwestern Usa, Donovan J. Craig, Jill Pacovsky Craig, Scott R. Abella

Vegetation Monitoring Presentations

For the last five years, roadside monitoring for exotic invasive species has been a common practice for documenting distributions in Clark County, Nevada (Abella et al., in press). Yet, studies have shown that weed relationships to road corridors differ depending upon the natural system (Hansen and Clevenger, 2005). In the Mojave Desert, it is unknown whether exotic species are limited to or even predominant along roadsides.

Compounding this uncertainty, fertile islands under shrubs are known to enhance conditions for many annuals (Thompson et al., 2005). Thus, a site’s shrub composition could influence exotic invasive plant distributions.

Implications For Management Prioritization Of Exotic Annual Weed Monitoring Near Roadsides In The Eastern Mojave Desert, Usa, Donovan J. Craig, Jill E. Craig, Scott R. Abella, Public Lands Institute,

Vegetation Monitoring Presentations

Invasive exotic plants provide an unnatural conduit for fires in the Mojave Desert. For the last five years, roadside monitoring for exotic invasive species has been a common practice for documenting distributions in Clark County, Nevada (Abella et al., in press). Yet, studies have shown that weed relationships to road corridors differ depending upon the natural system (Hansen and Clevenger, 2005). In the Mojave Desert, it is unknown whether exotic species are limited to or even predominant along roadsides.

Compounding this uncertainty, fertile islands under shrubs are known to enhance conditions for many annuals (Thompson et al., 2005). Thus, a …

Management Techniques For The Control Of Sahara Mustard (Brassica Tournefortii) In The Mojave Desert, Dianne N. Bangle, Scott R. Abella, Public Lands Institute,

Vegetation Monitoring Presentations

In the southwestern United States, Brassica tournefortii(Sahara mustard) is a highly invasive plant that colonizes roadsides, beaches, sand dunes, and open desert threatening native annuals. Sahara mustard is believed to contribute to fuel loads in the Mojave Desert in areas where Schismussp. and Bromussp. occur. Sahara mustard may act as ladder fuel, thereby facilitating the spread of fire throughout the landscape. Manpower limitations and insufficient funding limits the abilities of managers to effectively control Sahara mustard. We tested seed germinability in Sahara mustard after fruiting plants were treated with either 2%, 5%, or 12% triclopyr. Sahara mustard seed pods were …

Response Of Sahara Mustard (Brassica Tournefortii) To Water Addition And Soil Disturbance, Alexis Suazo, Jessica E. Spencer, Scott R. Abella

Vegetation Monitoring Presentations

Invasive exotic species can have a significant impact on the structure, function, and diversity of ecological communities. Sahara mustard (Brassica tournefortii) is one of the top exotic invasive species spreading through the southwestern deserts of North America. In arid environments, it is well documented that species abundance is sensitive to rainfall (Beatly 1974, Ernest et al. 2000). In the Mojave Desert, winter precipitation can trigger massive germination events (Beatly 1974). As a winter annual, Sahara mustard may have a positive response to winter precipitation by germinating, growing, and reproducing before native annuals, monopolizing soil moisture and nutrients, and potentially changing …

Mojave Applied Ecology Notes Winter 2008, Scott R. Abella, E. Cayenne Engel, Jill E. Craig

Mojave Applied Ecology Notes

Mojave Desert collaborative projects, fire history in Spring Mountains, Northshore Road rehabilitation, wildfires and invasive plants in American deserts conference, weed sentry surveys

Seeding Effectiveness And Natural Regeneration Of Mojave Desert Plant Communities After 2005-2006 Wildland Fires, E. Cayenne Engel, Scott R. Abella, Christina L. Lund

Fire Science Presentations

1) Assessment of BLM seeding effectiveness in mid-elevation burn where pre-burn plant communities were dominated by blackbrush, Joshua trees, and creosote.

2) Patterns driving fire recovery at the landscape scale:

• Link initial vegetation, environment, and soils
• Are there patterns that can be gleaned that can then be applied to management prescriptions?

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Quarterly Progress Report, October 1, 2007 To December 31, 2007, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• The Weed Sentry program surveyed more than 750 miles of federal lands in Clark County for invasive, exotic plant species.
• Weed Sentry also removed more than 600,000 individual invasive plants from federal
  lands. These removals represent pro-active efforts that may have forestalled large
  infestations difficult and costly to eradicate.
• In response to a request by the manager of the Fish and Wildlife Service Desert National
  Wildlife Refuge, a major effort of surveying springs for plant community composition
  and invasive plants provided unique knowledge services by the Weed Sentry program.
  No such baseline information existed for the Sheep Range. …

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Year-End Progress Report, October 1, 2006 To September 30, 2007, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• The Weed Sentry program surveyed more than 750 miles of federal lands in Clark County for invasive, exotic plant species.
• Weed Sentry also removed more than 600,000 individual invasive plants from federal
  lands. These removals represent pro-active efforts that may have forestalled large
  infestations difficult and costly to eradicate.
• In response to a request by the manager of the Fish and Wildlife Service Desert National
  Wildlife Refuge, a major effort of surveying springs for plant community composition
  and invasive plants provided unique knowledge services by the Weed Sentry program.
  No such baseline information existed for the Sheep Range. …

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Quarterly Progress Report, Period Ending March 31, 2007, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• Weed Sentry staff surveyed for exotic species on 208 miles of roads on NPS land and on 61 miles of BLM land. Due to sparse precipitation this winter, exotic species are much less abundant this year compared to last year at this time.
• Other exotic species projects initiated this quarter included an assessment of invasion patterns below native shrubs for early detection of potential invasion “hotspots,” and a community invasibility experiment established near the NPS nursery with substantial involvement from NPS ATR Ms. Alice Newton.
• A manuscript detailing several experiments with the invasive species Sahara mustard was submitted …

Vegetation Re-Establishment Of Mojave Desert Plant Communities After 2005-2006 Wildland Fires, E. Cayenne Engel, Scott R. Abella

Fire Science Presentations

Examine biotic and abiotic patterns that determine vegetative regrowth after wildfires to better inform land managers about what to expect after fires and how to manage restoration efforts.

Seeding Effectiveness For Eight Mojave Desert Perennials After A 2005 Wildfire, E. Cayenne Engel, Scott R. Abella, Christina L. Lund

Fire Science Presentations

To assess BLM seeding effectiveness in a mid-elevation burn where pre-burn plant communities were dominated by blackbrush, Joshua trees, and creosote.

Lake Mead National Recreation Area Vegetation Monitoring And Management: Quarterly Progress Report, Period Ending December 31, 2006, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• Two new Weed Sentry research assistants were hired.
• Weed Sentry staff surveyed for exotic species on 89 miles of roads on NPS and BLM land and treated more than 21,000 exotic plants in incipient populations.
• A grid-based rare plant monitoring method was tested this quarter.
• A manuscript detailing vegetation succession on a water pipeline at Lake Mead NRA was submitted for review to the journal Crossosoma.
• New integrative projects undertaken this quarter included establishing a competition study between a native grass and the exotic Sahara mustard, salvaging plants for research purposes from private sites with permission from landowners, …

Lake Mead National Recreation Area Vegetation Monitoring And Management: Final Close-Out Report, Time Period: October 1, 2005 To September 30, 2006, Margaret N. Rees

Vegetation Monitoring

The National Park Service (NPS) at Lake Mead National Recreation Area (LAME) entered into a cooperative agreement with the University of Nevada, Las Vegas (UNLV) to accomplish vegetation monitoring and management activities. This report summarizes activities that took place by UNLV under this task agreement between October 1, 2005, and September 30, 2006. The activities included:

• Weed Sentry mapping and treating incipient populations of exotic invasive plants throughout Clark County, including along shorelines of Lakes Mead and Mohave;
• Monitoring of targeted rare native plant species;
• Sahara mustard research; and
• Providing technical assistance upon request to the NPS vegetation manager.

In …

Lake Mead National Recreation Area Vegetation Monitoring And Management: Quarterly Progress Report, Period Ending December 31, 2005, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• Required reports on sticky buckwheat (Eriogonum viscidulum) and threecorner milkvetch (Astragalus geyeri var. triquetrus) to be submitted through appropriate protocols by December 30, 2005
• Summary report on several other rare plants to be submitted through appropriate protocols by December 30, 2005
• Invasive perennial pepperweed (also called tall whitetop; Lepidium latifolium) documented and treated by Weed Sentry within Black Canyon, Lake Mojave

Vegetation Characteristics Associated With Small Mammal Populations In The Las Vegas Wash, Christine Therese Herndon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Percent litter, average litter depth, percent bare ground, vegetation density, vegetation canopy, and distance to an ecotone boundary were measured and compared to small mammal capture locations in the Las Vegas Wash. Neotoma lepida appear to be greatly dependent upon the foliage litter of T. ramosissima. Alternatively, ecotone boundaries appear to be the most important factor affecting Dipodomys merriami distributions. Peromyscus eremicus distributions may be predicted based on vegetation density and increased canopy during shorter, winter torpor periods. Chaetodipus penicillatus were consistently associated with dense, seed-bearing vegetation, although C. penicillatus is extremely opportunistic and vegetation density should not limit their …

A Study Of Invasive Species Cover Near Roads In A Red Rock Canyon Blackbrush Community, Christopher Keough

UNLV Theses, Dissertations, Professional Papers, and Capstones

The monitoring of Mojave Desert plant communities during and following disturbance is an important process that could provide invaluable information about disturbance/recovery regimes in similar arid environments across the globe. Blackbrush communities are of particular interest because of their low replacement rate, which makes them highly susceptible to disturbance. Roads in the Mojave Desert have been associated with soil compaction resulting in a lack of vegetation as well as an increase in invasive species cover in the immediate proximity. To investigate these statements, eight fifty-foot line transects were established in each of three plot types (perpendicular to dirt roads, perpendicular …

Integrated Weed Management Plan For The Lower Las Vegas Wash, Elizabeth Bickmore

Publications (WR)

The Las Vegas Wash (Wash) is the primary drainage for the metropolitan Las Vegas Valley, eventually finding its way into the Colorado River watershed system. Pursuant to the recommendations of the Water Quality Citizens Advisory Committee, the Las Vegas Wash Coordination Committee (LVWCC) was formed in 1998 to develop a comprehensive plan for the long-term stabilization and management of the Wash. Consisting of representatives from 28 government agencies, businesses, environmental groups and citizens, the LVWCC formulated the Las Vegas Wash Comprehensive Adaptive Management Plan (CAMP) and designated the Southern Nevada Water Authority (SNWA) as the lead agency for the implementation …